When do I cut back pulmonaria?

After flowering in late April or May — cut the whole plant down to 5 cm above the ground. Three reasons: (1) tidies the spent flowers; (2) triggers a fresh flush of clean spotted foliage for summer display; (3) removes the older leaves that will inevitably develop powdery mildew. Water deeply after the cut. Late summer mildew: if the regrowth gets mildewed, cut again — pulmonaria recovers from multiple hard cuts in a season.

Why do pulmonaria flowers change colour from pink to blue?

Natural pH change in the petal anthocyanins as the flower ages. Newly-opened flowers are typically pink (more acidic petal sap); older flowers turn blue (more alkaline as sap matures). Both colours often appear on the same stem at different stages — the classic two-tone effect. Bee preference: bees visit the younger pink flowers (where nectar is) and ignore the older blue ones (effectively visual signalling for pollinators).

What's the best pulmonaria for the UK?

For white-themed gardens: Sissinghurst White — classic, vigorous, heavily silver-spotted leaves, pure white flowers. For mildew-resistance: Trevi Fountain — cobalt blue flowers, vigorous, much less prone to mildew than older cultivars. For silver foliage: Diana Clare — almost entirely silver leaves, dramatic. For pure blue: Blue Ensign — no pink phase, deep blue throughout. For a first pulmonaria, Trevi Fountain for reliability.

Why are my pulmonaria leaves covered in white powder?

Powdery mildew — the main UK pulmonaria disease. Three causes: drought stress, full sun, age of foliage. Treatment: cut the whole plant down to 5 cm — fresh regrowth is usually mildew-free. Prevention going forward: (1) move to a shadier position if currently too sunny; (2) mulch annually with leaf-mould and water deeply in dry spells; (3) replace with mildew-resistant cultivars (Trevi Fountain, Raspberry Splash, Excalibur) if persistent.

Will pulmonaria grow in deep shade?

Yes — one of the few flowering perennials that genuinely flourishes in deep shade. Pulmonaria thrives in north-facing borders, under deciduous trees, alongside shaded paths. Best display under deciduous trees where the plant gets spring sunlight before the canopy closes. In full shade: pulmonaria still flowers well; the silver leaf-spots are particularly striking against dark shade backgrounds.

Is pulmonaria good for wildlife?

Outstanding for early-emerging bumblebees. Pulmonaria is one of the first UK garden plants to flower (February–April) — exactly when queen bumblebees emerge from hibernation and desperately need nectar to start new colonies. A pulmonaria patch in late February attracts buff-tailed bumblebee queens, garden bumblebee queens, and a few honeybees on warmer days. The early nectar is critical for bumblebee colony survival; pulmonaria earns its garden place for this alone.

Pulmonaria / lungwort

Pulmonaria officinalis

Plant pulmonaria in autumn or spring, in part to full shade in moisture-retentive soil — they're hardy perennials grown for the distinctive silver-spotted oval leaves and small bell-shaped flowers that open pink and age to blue (sometimes both colours on the same stem). Pulmonaria is hardy (RHS H6–H7) and one of the earliest flowering UK perennials, blooming from late February through April when little else is yet awake. The flowers are an important early nectar source for emerging queen bumblebees. Cut the whole plant down to 5 cm after flowering for a fresh flush of clean foliage — old summer leaves get mildewed and tatty. Sissinghurst White (pure white flowers, heavily silver-spotted leaves) is the UK garden classic. Spreads gently by underground rhizomes; divide every 3–4 years.

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